Efficient continuous flow irrigation endoscope

ABSTRACT

A user friendly, safe and efficient continuous flow irrigation endoscope having only a single housing sheath without an inner sheath. The exclusion of the inner sheath increases the effective lumen of the endoscope. A long hollow cylindrical tube, capable of performing a to and fro and rotary motion, is placed inside the housing sheath to function as an endoscopic instrument, but also to serve as a conduit for evacuating waste fluid and detached tissue pieces present inside a tissue cavity. A single inflow port located at the proximal end of the single housing sheath allows the irrigation fluid to enter the tissue cavity via the lumen of the said housing sheath. The invented endoscope system has a single inflow port, a single outflow port, without an inner sheath so that all waste fluid and tissue debris present inside cavity are evacuated via the same single outflow port. No type of feedback mechanism, such as mechanical or electrical feedback mechanism, is incorporated in the endoscope to facilitate the removal of detached tissue pieces or waste fluid.

CROSS-REFERENCE TO RELATED APPLICATIONS

This is a divisional of application Ser. No. 11/869,470, filed on Oct.9, 2007, which claims the benefit of Indian Provisional PatentApplication No. 2236/DEL/2006, filed on Oct. 11, 2006, the entiredisclosures of which are incorporated by reference herein.

FIELD OF THE INVENTION

The present invention relates to surgeries and, in particular, toendoscopic procedures which deploy continuous flow irrigation, such ashysteroscopic fibroid morcellation, trans uretheral prostatemorcellation, hysteroscopic polyp morcellation, hysteroscopicseptoplasty, hysteroscopic adhesiolysis, trans uretheral morcellation ofbladder tumors and arthroscopy.

BACKGROUND OF THE INVENTION

Continuous flow endoscopes are frequently used in endoscopic proceduressuch as hysteroscopy, trans uretheral urologic endoscopic procedures andarthroscopy. Those skilled in the art would know the structuralcomposition of a continuous flow irrigation endoscope. In thisapplication, the term “continuous flow irrigation” means that fluidsimultaneously enters and escapes from a tissue cavity via separateentry and exit points, as a result of which positive fluid pressure iscreated inside the tissue cavity which distends the cavity. A continuousflow irrigation endoscope generally comprises an inner sheath which isplaced inside the cylindrical lumen of an outer sheath. The sheaths arehollow cylindrical tubes which have a distal end which enters a tissuecavity, and a proximal end on which an inflow or outflow port isattached for the purpose of instilling or evacuating fluid from thecavity. The irrigation fluid is instilled via an inflow port.

In many prior art systems, the instilled fluid travels through the lumenof the inflow sheath and enters the tissue cavity via the distal openingof the inflow sheath. The waste fluid present inside the tissue cavityenters into a potential space present between the outer and the innersheaths via multiple holes present near the distal end of the outersheath and this waste fluid is finally evacuated via the outflow portattached at the proximal end of the outer sheath. A fiber optictelescope is placed inside the cylindrical lumen of the inner sheath, toview the interior of the tissue cavity. An endoscopic instrument canalso be introduced via the lumen of the inner sheath. In this paragraph,the terms “outer sheath” and “inner sheath” refer to hollow cylindricaltubes which participate in maintaining the structural integrity of theendoscope, and such tubes also cannot move relative to each other. Also,the endoscopic instrument frequently moves relative to the outer and theinner sheaths. Various different types of “continuous flow irrigationendoscopes” have been described in U.S. Pat. Nos. 3,835,842; 5,320,091;5,392,765; 5,807,240; and U.S. Patent Appln. Publ. Nos. 2003/0130565 A1(Jul. 10, 2003); 2006/0041186 A1 (Feb. 23, 2006); and 2006/0122459 A1(Jun. 8, 2006).

The arrangement described in the preceding paragraph has two majordisadvantages which are negated by the system of the proposed invention.The disadvantages are as follows:

One disadvantage is that detached tissue pieces, larger than a criticalsize, present in the tissue cavity are unable to pass through thepotential space between the outer and the inner sheaths. Thus, inendoscopic procedures the entire endoscope or the “endoscopicinstrument” has to be repeatedly removed from the tissue cavity in orderto evacuate the detached tissue pieces present inside the tissue cavity,and this increases the risk of complications like perforation, excessivebleeding and also increases the surgical time. As described in EP0996375, U.S. Pat. No. 7,249,602 and U.S. Patent Appln. Publ. No.2006/0047185, it may be argued that, instead of one outflow port, twooutflow ports be installed via suitable mechanical means at suitablelocations in the endoscope, one outflow port for primarily evacuatingthe waste fluid from the cavity and the other outflow port being meantto primarily evacuate the resected or cut tissue. However, such anarrangement is not desirable since it necessitates the incorporation oftwo out flow channels instead of one and it also tends to increase theoverall weight of the endoscope. The system of the present inventionsolves all the problems described in this paragraph by utilizing onlyone single outflow port, attached to a single outflow channel, whichserves to evacuate both detached tissue pieces and waste fluid from thetissue cavity in a continuous irrigation manner.

The other disadvantage is that the inner sheath, by virtue of occupyingadditional space, reduces the effective lumen diameter of the endoscopewhich necessitates a reduction in the thickness or size of the“endoscopic instrument” or the telescope or both. The system of thepresent invention reduces the problem mentioned in this paragraph byutilizing only one housing sheath and by utilizing special type ofendoscopic instrument which additionally also functions as the soleoutflow channel for simultaneously removing waste fluid and detachedtissue pieces. In U.S. Pat. No. 6,824,544, waste fluid and tissue piecesare evacuated via an inflow sheath and the tissue is resected by aseparate endoscopic instrument, loop, which cannot participate inremoval of waste fluid or tissue pieces; both these features beingcontrary to the principals of the present invention.

Also, unlike U.S. Pat. No. 6,824,544, in the present invention, a singleoutflow channel (that is suction channel) is not bifurcated at the levelof the endoscope and any type of valve, simple or solenoid operated, isnot attached to the outflow channel. Also, unlike U.S. Pat. No.6,824,544, in the present invention, a controller is not used forinfluencing or regulating the working of the endoscope, for example byway of controlling the opening and closing motion of solenoid valves.This paragraph describes requirements which essentially need to befulfilled by the system of the present invention. These requirementshave been imposed so that the use of the invented endoscope is notrestricted to any specific type of fluid management system with acontroller, so that only one outflow tube is needed to be connected tothe endoscope, such that the endoscope is simple, light and userfriendly.

In the present invention, the diameter or area of cross section of theinner lumen of a single outflow port needs to be at least equal to thediameter or area of cross section of the outflow channel, so thatdetached tissue pieces and waste fluid could be evacuated in the mostefficient manner. Thus, in the present invention, unlike in EP 0996375,U.S. Pat. No. 7,249,602 and U.S. Patent Appln. Publ. No. 2006/0047185, avalve is not attached to the outflow channel for controlling thepressure or the fluid flow.

The present invention is essentially a continuous flow irrigationendoscope which cannot function if the single outflow channel isblocked, for example by an opening or closing valve. Thus, in thepresent invention, unlike in EP 0996375, U.S. Pat. No. 7,249,602 andU.S. Patent Appln. Publ. No. 2006/0047185, an opening or closing valveis not attached to the outflow channel.

OBJECT OF THE INVENTION

An object of the invention is to provide a continuous flow irrigationendoscope system in which the detached tissue pieces and waste fluidpresent inside a tissue cavity are evacuated in a continuous manner fromthe tissue cavity, without the need of removing the entire endoscope ora part of the endoscope from the tissue cavity.

Another object of the invention is to provide a continuous flowirrigation endoscope system in which both the detached tissue pieces andwaste fluid are simultaneously evacuated in a continuous manner from thetissue cavity via a same single outflow port connected to a singleoutflow channel.

Another object of the invention is to provide a continuous flowirrigation endoscope system in which both the detached tissue pieces andwaste fluid are simultaneously evacuated in a continuous manner from thetissue cavity via a same single outflow port, such that no mechanical orelectrical feedback mechanism, or a valve of any type or a controller,is utilized for evacuating the detached tissue pieces or waste fluid.

Another object of the invention is to provide a continuous flowirrigation endoscope system to which only a single outflow tube needs tobe connected.

Another object of the invention is to provide a continuous flowirrigation endoscope system in which the diameter or area of crosssection of the inner lumen of the outflow port is at least equal to thediameter or area of cross section of the outflow channel.

Another object of the invention is to provide a continuous flowirrigation endoscope system which is relatively light in weight.

Another object of the invention is to provide a continuous flowirrigation endoscope system which is user friendly, safe and efficient.

BRIEF SUMMARY OF THE INVENTION

The present invention provides a continuous flow irrigation endoscopesystem in which both the waste fluid and tissue are removed from thetissue cavity via a same single outflow port. The system comprises along hollow cylindrical tube open at both ends, the tube being placedinside the long cylindrical lumen of an outer housing sheath. The tubefunctions as an endoscopic instrument and also acts as a conduit forremoving waste fluid and detached tissue from the tissue cavity. Aninflow port is attached at the proximal end of the housing sheath forinstilling fluid into a tissue cavity, while the proximal open end ofthe hollow cylindrical tube functions as an outflow port for theevacuation of detached tissue pieces and waste fluid.

The present invention also provides a method of conducting surgeryemploying a continuous flow irrigation endoscope system. The methodcomprises the steps of: providing a continuous flow irrigation endoscopesystem in the vicinity of a surgical site; and removing waste fluidand/or tissue debris from the surgical site with the endoscope, withoututilizing any kind of a feedback mechanism or valve system tofacilitate, affect or influence the evacuation or removal of tissueand/or waste fluid from the surgical site.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 describes the basic layout of the system of the presentinvention.

FIG. 2 is a cross-sectional view of the system of FIG. 1 taken alongline A-A of FIG. 1.

DETAILED DESCRIPTION OF THE INVENTION

The present invention relates to a continuous flow irrigation endoscopein which the detached tissue pieces and waste fluid present inside atissue cavity are automatically evacuated, in a continuous manner,without withdrawing the endoscope or any part of the endoscope from thetissue cavity.

The basic layout of the invented endoscope is shown in FIG. 1. Theendoscope 1 has a distal end 2 which enters a tissue cavity and aproximal end 3 which lies outside the tissue cavity. The inventedendoscope comprises an externally located “housing sheath” 4, an opticalsystem 5 and a hollow cylindrical tube like instrument 6.

Again referring to FIG. 1, unlike many prior art systems, the inventedsystem does not have a separate inner sheath, and a single sheath hasbeen termed as “housing sheath” 4. The housing sheath 4 has an inflowport 7 located near its proximal end 3. Sterile irrigation fluid meantfor distending a body tissue cavity is instilled via the inflow port 7in the direction of the arrow 8. The irrigation fluid travels throughthe lumen 9 of the housing sheath 4 and finally enters the tissue cavityvia a “distally located opening” 10 of the housing sheath 4. The crosssection of the “distally located opening” 10 and or the cross section ofthe housing sheath 4 could also be oval in shape.

Again referring to FIG. 1, a hollow cylindrical tube like instrument 6has been placed inside the lumen 9 of the housing sheath 4. For brevity,the hollow cylindrical tube like instrument 6 shall be referred to as“instrument” 6. The instrument 6 is a hollow cylindrical tube likestructure having a distal opening 14, a lumen 15 and a proximallylocated opening which is being termed as the outflow port 16. The lumendiameter of the outflow port 16 is about the same as the lumen diameterof the rest of the instrument 6. The lumen diameter of the outflow port16 could also be less than the lumen diameter of the rest of theinstrument 6, but such an arrangement may retard the evacuation ofdetached tissue pieces. The waste fluid and the detached tissue piecespresent inside the tissue cavity enter the lumen 15 of the instrument 6through the distal opening 14 and travel in the direction of the arrow17. The waste fluid and the detached tissue pieces are finally evacuatedvia the outflow port 16. Depending upon the surgical requirement, thecross section of lumen 15 could also be oval, or of any other shape.

As shown in FIG. 2, the effective cross sectional area of the housingsheath 4 should be preferably less than the effective cross sectionalarea of the instrument 6, as such an arrangement would facilitate theevacuation of detached tissue pieces. In this application, the term“effective cross sectional area” of the housing sheath 4 relates to thetotal cross sectional area of the housing sheath 4 from which the crosssectional area occupied by the instrument 6 and the optical channel 13has been subtracted. The cross sectional area of the instrument 6 isdenoted by the cross sectional area of the lumen 15 of the instrument 6.

The instrument 6 is placed inside the housing sheath 4 by virtue of afluid tight contact. Also, those skilled in the art would know thatgenerally an obturator is inserted inside the housing sheath subsequentto which the housing sheath is inserted into a tissue cavity. However,the obturator assembly has not been included in the drawing, forsimplicity.

Again referring to FIG. 1, the optical system 5 comprises a telescopeeyepiece 12 which is connectable to a video camera, an optical channel13 which contains fiber optic bundles and a distal viewing tip 11 forvisualizing the interior of the tissue cavity. In a exemplaryembodiment, the optical channel 13 is not straight and has beendeliberately provided with a bend 18. The optical channel 13 and thebend 18 are placed inside the lumen 9 of the housing sheath 4 andoutside the lumen 15 of the instrument 6. In case the bend 18 is placedoutside the lumen 9 of the housing sheath 4, then the fragile opticalchannel 13 could easily break at the bend 18. The bend 18 has beenincluded to provide additional space for the instrument 6, especially ifthe instrument 6 is a hysteroscopic or urologic morcellator, or anarthroscopic shaver, in which cases additional space is needed toaccommodate the driving mechanism of the morcellator or the shaver. Theoptical channel could also be straight but such an arrangement may notallow the incorporation of the said morcellator or a shaver. Also, thelight source arrangement for the optical system 5 has not been includedin FIG. 1 for simplicity.

Again referring to FIG. 1, the instrument 6 could be morcellator forhysteroscopic fibroid resection or for cutting a prostate adenoma inurologic endoscopic procedures. The instrument 6 could also be a shaverto be used in arthroscopic surgeries. The morcellator or the shaver havenot been separately shown but the hollow inner channels of both arerepresented by the lumen 15 of the instrument 6. Also, those skilled inthe art would understand that a window opening corresponding with thedistal opening 14 is present near the distal end of hysteroscopicmorcellators and shavers, wherein two cutting edges incorporated in tworotatable tubes facilitate tissue cutting in the region of the window.If the window is kept in the open position while the morcellator or theshaver is not operating, then the same would allow continuous flowirrigation all through the endoscopic procedure, that is, even while themorcellator or shaver is non functional. The instrument 6 could also bea simple cutting knife wherein the distal end of the instrument 6 wouldbe required to be shaped like a conventional knife. The knife could alsofunction as a monopolar electrosurgical instrument. The instrument 6could also be an electrode such as a ball electrode for ablating theendometrium, a prostate adenoma or a bladder tumor. The ball electrode,unlike the prior art ball electrodes, would have centrally placed ahollow cylindrical channel via which waste fluid and detached tissuegenerated during ablation could be evacuated.

Again referring to FIG. 1, and according to an exemplary embodimentonly, it is important to note that instrument 6 may be configured tomove in a to and fro direction relative to, and parallel to, thelongitudinal axis of the housing sheath 4. The instrument 6 may be alsocapable of rotating around the longitudinal axis of the instrument 6 ineither direction. Suitable mechanical means not shown in any figure aredeployed to facilitate the to and fro movement and the rotary movementof the instrument 6. The distal opening 14 of the instrument 6 may alsobe cut obliquely such that opening 14 is oval instead of being round.

Again referring to FIG. 1, the proximal part of the instrument 6 couldalso be provided with a “bend” similar to the bend 18 provided in theoptical channel 13, and such bend could be located inside or outside thelumen 9 of the housing sheath 4. However, such an arrangement couldretard the evacuation of detached tissue pieces.

Referring to FIG. 1, the relative locations of the optical channel 13and the instrument 6 could even be interchanged with respect to eachother or with respect to the inflow port 7.

Referring again to FIG. 1, the entire instrument 6, from the distalopening 14 to the proximally located outflow port 16, may comprise ametal, a rigid plastic material, a ceramic material, or a combination ofthe same, for example.

The outlet of instrument 6 has been termed as “outflow port” 16 only forsake of an easier description. In the prior art continuous flowendoscopes, the term “outflow port” is commonly referred to an outletattachment which is attached at the proximal end of an outer or an innersheath. Also, in the prior art systems the sheaths are immovablerelative to each other, they do not function as an instrument, theirpurpose being only to provide structural integrity to the endoscope andto provide channels for instilling or removing fluid from a tissuecavity. However, in the present invention the so-called “outflow port”is attached at the proximal end of the movable instrument 6, theinstrument not being meant to impart structural integrity to theendoscope; the instrument can also be replaced by a different type ofinstrument depending upon the surgical requirement.

Referring to FIG. 1, it is also important to note that no feedbackmechanism, no valves and no valve-like system have been providedanywhere in the endoscope 1 for facilitating, affecting or influencingthe evacuation of detached tissue pieces and waste fluid in any manner.It is important to note that the proximal end of the instrument 6 hasnot been bifurcated in any manner. This means that the outlet port 16 isconnectable to only a single outflow tube which would transport thedetached tissue pieces and the waste fluid to a waste collectingcontainer not shown in any figure. The outflow tube may be made offlexible resilient polymeric material. If at all any bifurcation, valvesystem or a feedback mechanism, as explained in this paragraph, needs tobe installed, then the same could be installed only in the outflow tube,sufficiently away from the endoscope 1, such that the installation doesnot enhance the weight of the endoscope because “low weight” of theendoscope is one of the objectives of the invention.

In the preceding paragraphs, it might be misinterpreted that theinstrument 6 is primarily meant to act as an outflow channel forevacuating waste fluid and detached tissue pieces from a tissue cavity.However, the primary aim of the instrument 6 is to act as an endoscopicinstrument while the hollow cylindrical lumen 15 of the instrument 6simply provides a passage for the evacuation of detached tissue piecesand waste fluid.

The invention is useful because it allows evacuation of detached tissuepieces present in a tissue cavity during endoscopic procedures deployingcontinuous flow irrigation, and without the need of withdrawing theendoscope or a part of the endoscope from the tissue cavity.

Although the present invention has been described in connection withpreferred embodiments, many modifications and variations will becomeapparent to those skilled in the art. While preferred embodiments of theinvention have been described and illustrated above, it should beunderstood that these are exemplary of the invention and are not to beconsidered as limiting. Accordingly, it is not intended that the presentinvention be limited to the illustrated embodiments, but only by theappended claims.

What is claimed as new and desired to be protected by Letters Patent ofthe United States is:
 1. A method of surgery, comprising the steps of:providing a continuous flow endoscope comprising: a single housingsheath without a separate inner sheath having a longitudinal axis, adistal end and a proximal end, said single housing sheath being tubularalong its entire length; a movable tube located at least partiallywithin the single housing sheath, the movable tube being configured tocut tissue and evacuate the cut tissue therethrough, the movable tubehaving a longitudinal axis and a lumen extending between opposite distaland proximal ends of the moveable tube, the lumen providing a passagefor evacuation of waste fluid and tissue in a tissue cavity during anendoscopic procedure deploying continuous flow irrigation, wherein themovable tube is a morcellator provided with a morcellator window that isconfigured to directly cut intact living tissue of the tissue cavity byvirtue of the morcellator window being in direct apposition with theintact living tissue and evacuate the cut tissue; an inflow port locatedat the proximal end of the single housing sheath, the inflow port beingformed on an outer circumferential portion of the single housing sheathand in contact with the single housing sheath; and an outflow portlocated at the proximal end of the movable tube and located outside thesingle housing sheath, the outflow port being an opening disposed on thelongitudinal axis of the moveable tube and facing away from the distalend of the moveable tube, and the area of cross section of the openingof the outflow port being at least equal to the area of cross section ofthe lumen of the movable tube; injecting fluid into the single housingsheath through the inflow port, thereby allowing the fluid to enter thetissue cavity; moving the entire movable tube in both a linear motionand a rotary motion relative to the longitudinal axis of the singletubular housing sheath; cutting tissue in the tissue cavity using thedistal end of the moveable tube; and evacuating the entire waste fluidand cut tissue from the tissue cavity directly through the opening ofthe outflow port of the movable tube without using a feedback mechanismor a valve system to evacuate the waste fluid and cut tissue.
 2. Themethod of claim 1, further comprising an optics channel located withinthe single housing sheath, the optics channel having a bent region whichforms an angle with the longitudinal axis of the single housing sheath,the bent region is located inside of the single housing sheath.
 3. Themethod of claim 1, further comprising the step of connecting an outflowtube to the outflow port.
 4. The method of claim 1, wherein the singlehousing sheath has an effective cross sectional area less than aneffective cross sectional area of the movable tube, wherein theeffective cross sectional area of the single housing sheath is the totalcross sectional area of the housing sheath from which the crosssectional area occupied by the movable tube and the optics channel hasbeen subtracted and the effective cross sectional area of the movabletube is the cross sectional area of the lumen of the movable tube. 5.The method of claim 1, wherein the step of moving the entire movabletube in both a linear motion and a rotary motion relative to thelongitudinal axis of the single tubular housing sheath is after the stepof injecting the fluid into the single housing sheath.
 6. A method ofsurgery, comprising the steps of: providing a continuous flow endoscopecomprising: a single housing sheath without a separate inner sheathhaving a longitudinal axis, a distal end and a proximal end, said singlehousing sheath being tubular, a movable tube located at least partiallywithin the single housing sheath, the movable tube being configured tocut tissue and evacuate the cut tissue therethrough, the movable tubehaving a longitudinal axis and a lumen extending between opposite distaland proximal ends of the moveable tube, the lumen providing a passagefor evacuation of waste fluid and tissue in a tissue cavity during anendoscopic procedure deploying continuous flow irrigation, wherein themovable tube is a morcellator that is configured to cut intact livingtissue of the tissue cavity, an inflow port located at the proximal endof the single housing sheath, and an outflow port located at theproximal end of the movable tube and located outside the single housingsheath and the area of cross section of the opening of the outflow portbeing at least equal to the area of cross section of the lumen of themovable tube; injecting fluid into the single housing sheath through theinflow port, thereby allowing the fluid to enter the tissue cavity;moving the entire movable tube in both a linear motion and a rotarymotion relative to the longitudinal axis of the single tubular housingsheath; cutting tissue in the tissue cavity using the distal end of themoveable tube; and evacuating the entire waste fluid and cut tissue fromthe tissue cavity directly through the opening of the outflow port ofthe movable tube without using a feedback mechanism or a valve system toevacuate the waste fluid and cut tissue.
 7. The method of claim 6,wherein the inflow port is formed as part of an outer circumferentialportion of the single housing sheath.
 8. The method of claim 6, whereinthe outflow port is an opening disposed on the longitudinal axis of themoveable tube and facing away from the distal end of the moveable tube.9. The method of claim 6, wherein the single housing sheath has aneffective cross sectional area less than an effective cross sectionalarea of the movable tube, wherein the effective cross sectional area ofthe single housing sheath is the total cross sectional area of thehousing sheath from which the cross sectional area occupied by themovable tube and the optics channel has been subtracted and theeffective cross sectional area of the movable tube is the crosssectional area of the lumen of the movable tube.
 10. The method of claim6, wherein the step of moving the entire movable tube in both a linearmotion and a rotary motion relative to the longitudinal axis of thesingle tubular housing sheath is after the step of injecting the fluidinto the single housing sheath.
 11. The method of claim 6, wherein themorcellator is provided with a morcellator window that is configured todirectly cut the intact living tissue of the tissue cavity by virtue ofthe morcellator window being in direct apposition with the intact livingtissue.
 12. The method of claim 6, further comprising an optics channellocated within the single housing sheath, the optics channel has a bentregion which forms an angle with the longitudinal axis of the singlehousing sheath, the bent region is located inside of the single housingsheath.
 13. The method of claim 6, further comprising the step ofconnecting an outflow tube to the outflow port.